docs: def critical_value(n, p):
      """
      This function calculates the critical value given
      n and p, and confidence level = 1 - p.
      """
      dn = 1
      delta = 0.5
      res = ROOT.TMath.KolmogorovProb(dn * sqrt(n))
      while res > 1.0001 * p or res < 0.9999 * p:
          if (res > 1.0001 * p):
              dn = dn + delta
          if (res < 0.9999 * p):
              dn = dn - delta
          delta = delta / 2.
          res = ROOT.TMath.KolmogorovProb(dn * sqrt(n))
      return dn